Thread (19 messages) 19 messages, 3 authors, 2017-01-20
STALE3426d
Revisions (7)
  1. v1 [diff vs current]
  2. v2 [diff vs current]
  3. v3 [diff vs current]
  4. v4 current
  5. v5 [diff vs current]
  6. v6 [diff vs current]
  7. v7 [diff vs current]

[PATCH v4 04/14] sata: ahci-da850: get the sata clock using a connection id

From: Bartosz Golaszewski <hidden>
Date: 2017-01-19 13:36:14
Also in: linux-devicetree, linux-ide, lkml
Subsystem: libata subsystem (serial and parallel ata drivers), the rest · Maintainers: Damien Le Moal, Niklas Cassel, Linus Torvalds

In preparation for using two clocks in the driver (the sysclk2-based
clock and the external REFCLK), check if we got a functional clock
after calling ahci_platform_get_resources(). If not, retry calling
clk_get() with con_id specified.

Signed-off-by: Bartosz Golaszewski <redacted>
---
 drivers/ata/ahci_da850.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)
diff --git a/drivers/ata/ahci_da850.c b/drivers/ata/ahci_da850.c
index 267a3d3..8cfdc86 100644
--- a/drivers/ata/ahci_da850.c
+++ b/drivers/ata/ahci_da850.c
@@ -71,12 +71,28 @@ static int ahci_da850_probe(struct platform_device *pdev)
 	struct ahci_host_priv *hpriv;
 	struct resource *res;
 	void __iomem *pwrdn_reg;
+	struct clk *clk;
 	int rc;
 
 	hpriv = ahci_platform_get_resources(pdev);
 	if (IS_ERR(hpriv))
 		return PTR_ERR(hpriv);
 
+	/*
+	 * Internally ahci_platform_get_resources() calls clk_get(dev, NULL)
+	 * when trying to obtain the first clock. This SATA controller uses
+	 * two clocks for which we specify two connection ids. If we don't
+	 * have a clock at this point - call clk_get() again with
+	 * con_id = "sata".
+	 */
+	if (!hpriv->clks[0]) {
+		clk = clk_get(dev, "sata");
+		if (IS_ERR(clk))
+			return PTR_ERR(clk);
+
+		hpriv->clks[0] = clk;
+	}
+
 	rc = ahci_platform_enable_resources(hpriv);
 	if (rc)
 		return rc;
-- 
2.9.3
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help